The present invention relates to a blowing apparatus for removing soot, comprising a tubular lance.
In known blowing apparatus comprising a lance, blast jets, which issue out of nozzles of the lance and serve for cleaning heating surfaces, describe helicoidal paths which always assume the same position in space. Hereby, there is a danger that the heating surface is engaged by the blast jet at the same place during each blasting operation. In particularly unfavourable circumstances, damage can occur through erosion by constantly repeated blasting.
It is an object of the present invention to provide a blowing apparatus in which the position of the blast jets in space and thereby also relative to the heating surfaces to be cleaned can be displaced during each blasting operation.